Wipe the meat and remove all the fat. Cut the meat into pieces about 2 in. by 2½ in. Heat the fat in a stewpan until smoking hot and fry the meat until brown. Remove the meat and fry the sliced onions. Then add the flour and cook, stirring until brown. Add 1¼ pt. water and bring to the boil, stirring constantly. Simmer for a few minutes. Add the vinegar and seasoning, return the meat and simmer gently for about 2 hr. Mix the ingredients for the savoury balls together, bind with the egg or milk into a stiff mixture and make into 12 balls. Bring the stew to boiling-point about 30 min. before time for serving and drop in the balls. Simmer for the remainder of the time. Pile the meat in the centre of a hot dish, pour the gravy over and arrange the balls neatly round the base.